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2023.03.23

Active Galactic Nuclei: Monsters to Scale or Puzzles to Solve?

<p>Active Galactic Nuclei (AGNs) are the brightest sources of electromagnetic radiation in the&nbsp;universe, enabling us to observe them across the cosmos. AGNs are the central parts of galaxies.Most of their brightness results from the accretion of matter by a supermassive black hole&nbsp;(SMBH) at their center. Studying the AGNs informs us about the role of SMBHs in the&nbsp;formation and evolution of galaxie...</p>

2023.05.17

脉冲星自转减慢和高速中子星：中子超流涡旋体的中微子辐射及其效应

<p>1)首先介绍近年来脉冲星观测的(P-Pdot)图同国际流行的脉冲星自转减慢的磁偶极辐射理论(标准模型)预言的明显矛盾。其次介绍1982年我们提出的中子超流涡旋体的中微子辐射理论模型。2) 在1982年我们的理论基础上,我们提出了这五十年来天文观测发现的高速中子星的物理起源于我们的 “中子超流涡旋体的中微子辐射喷流模型”。Host: Tipei L</p>

2023.03.09

Re-investigating A Puzzle in Kepler Planets

<p>super-Earths and mini-Neptunes (shortened as &#39;kepler planets&#39;) are the most abundant type of planets known to us. Currently, their formation channel is under debate.In this talk, I will discuss our attempt to solve a small puzzle in the observations of these planets. We were led to claim that, after formation, each of these planets have scattered and digested a few Mars-massed objects. The smal...</p>

2023.03.16

Microphysical and non-thermal processes in the circumgalactic medium: turbulence, magnetic fields and cosmic rays

<p>Multiphase gas structure is ubiquitous in our universe. Recent observations suggest that large quantities of cool (10^4 K) gas are detected in the circumgalactic medium (CGM) of galaxy halos, which extends up to a few times of galactic virial radius. In addition, warm gas at a few 10^5 K is found to be tightly associated with the star-forming galaxies, but not the quenched ones. However, the or...</p>

2023.03.02

The variation of the stellar initial mass function (IMF) with metallicity and time

<p>The stellar IMF is one of the most important astrophysical distributions and plays vital role in galactic astronomy. Both constant and variable IMFs across different environments have been claimed despite a large number of theoretical and observational efforts. However, the measurement of the IMF in Galactic stellar populations has been limited by the relatively small number of photometrically ...</p>

2023.02.23

Solar-like Oscillations: Past, Present, & Future

<p>The analysis and interpretation of stellar oscillations ---asteroseismology --- permits direct observational examination of stellar interiors. In particular, low-degree p-modes, excited through the same&nbsp;stochastic convective mechanism as in our Sun, permit us to draw&nbsp;inferences about the global properties, interior structures, rotational&nbsp;dynamics, and evolutionary fates of field stars. Space-ba...</p>

2022.12.29

Cosmology with 3D maps of the Universe

<p>The spatial clustering of large-scale structures (LSS) offers insights into the expansion history of the Universe and the growth of structures, and are foreseen to tackle the mysteries of the dark energy and dark matter. Precise cosmological constraints with clustering measurements require the 3-D positions (2-D angular position and redshift) of numerous tracers, and a large sample volume. To t...</p>

2022.12.27

Universe seen through weak gravitational lensing

<p>We are facing an exciting era of discovering the nature of dark matter and dark energy with upcoming large-scale surveys, such as Chinese Survey Space Telescope (CSST), Rubin, and Euclid. One of the major analysis methods of the surveys, weak lensing (WL), uses the shape distortion of background sources for detecting the foreground matter distribution. It is a powerful method for studying dark ...</p>

2023.01.04

Mapping Interstellar Magnetic Field Strength in the Era of FAST, FASTA, and SKA

<p>Magnetic field is one of the most important physical quantities regulating the evolution of interstellar medium and star formation in the Milky Way. Despite enormous surveys using techniques of dust polarization, Faraday rotation, and synchrotron polarization to reveal the magnetic field structure of the Milky Way, none of the techniques can give accurate magnetic field strength. Zeeman effect ...</p>

2023.01.03

On Modelling Complex Systems in Astronomy

<p>Astronomy today is fundamentally different than it was even just a decade ago. Our increasing ability to collect a large amount of data from ever more powerful instruments has enabled many new opportunities. However, such an opportunity also comes with new challenges. The bottleneck stems from the fact that most astronomical observations are inherently high dimension — from “imaging” the Uni...</p>